--- linux-2.2.10/include/linux/serialP.h Tue May 11 19:35:44 1999 +++ linux-2.2.10-ub/include/linux/serialP.h Thu Aug 5 22:21:54 1999 @@ -61,6 +61,7 @@ struct tty_struct *tty; int read_status_mask; int ignore_status_mask; + int wakeup_reason; int timeout; int quot; int x_char; /* xon/xoff character */ --- linux-2.2.10/include/asm-i386/termios.h Wed Mar 24 20:45:59 1999 +++ linux-2.2.10-ub/include/asm-i386/termios.h Thu Aug 5 20:43:48 1999 @@ -36,6 +36,25 @@ #define TIOCM_OUT1 0x2000 #define TIOCM_OUT2 0x4000 +/* +** ioctl(fd, TIOCMIWAIT, condition) (wait for serial interrupt) +** condition flags are defined as bitwise OR of the values below. +** If TIOCMIWAIT_RETFLAGS is specified, these flags are also the +** indicate the triggering condition on return. +** ioctl(fd, TIOCMIWAIT, 0) will clear any current conditions +** and return immediately with return value indicating the conditions. +*/ +#define TIOCMIWAIT_RNG TIOCM_RNG +#define TIOCMIWAIT_DSR TIOCM_DSR +#define TIOCMIWAIT_DCD TIOCM_CD +#define TIOCMIWAIT_CTS TIOCM_CTS +#define TIOCMIWAIT_RX 0x1000 +#define TIOCMIWAIT_BRK 0x2000 +#define TIOCMIWAIT_TX 0x4000 +#define TIOCMIWAIT_ERR 0x8000 + +#define TIOCMIWAIT_RETFLAGS 0x800000 + /* ioctl (fd, TIOCSERGETLSR, &result) where result may be as below */ /* line disciplines */ --- linux-2.2.10/drivers/char/serial.c Tue Mar 23 22:13:58 1999 +++ linux-2.2.10-ub/drivers/char/serial.c Thu Aug 5 22:34:58 1999 @@ -17,7 +17,7 @@ * * rs_set_termios fixed to look also for changes of the input * flags INPCK, BRKINT, PARMRK, IGNPAR and IGNBRK. - * Bernd Anhäupl 05/17/96. + * Bernd Anhäupl 05/17/96. * * 1/97: Extended dumb serial ports are a config option now. * Saves 4k. Michael A. Griffith @@ -32,6 +32,8 @@ * 4/98: Added changes to support the ARM architecture proposed by * Russell King * + * 03/99: TIOCMIWAIT enhanced by Michael McCormack + * * This module exports the following rs232 io functions: * * int rs_init(void); @@ -154,7 +156,7 @@ #endif static char *serial_name = "Serial driver"; -static char *serial_version = "4.27"; +static char *serial_version = "4.27b"; static DECLARE_TASK_QUEUE(tq_serial); @@ -402,12 +404,18 @@ if (*status & UART_LSR_BI) { *status &= ~(UART_LSR_FE | UART_LSR_PE); icount->brk++; - } else if (*status & UART_LSR_PE) + info->wakeup_reason |= TIOCMIWAIT_BRK; + } else if (*status & UART_LSR_PE) { icount->parity++; - else if (*status & UART_LSR_FE) + info->wakeup_reason |= TIOCMIWAIT_ERR; + } else if (*status & UART_LSR_FE) { icount->frame++; - if (*status & UART_LSR_OE) + info->wakeup_reason |= TIOCMIWAIT_ERR; + } + if (*status & UART_LSR_OE) { icount->overrun++; + info->wakeup_reason |= TIOCMIWAIT_ERR; + } /* * Now check to see if character should be @@ -453,6 +461,9 @@ *status = serial_inp(info, UART_LSR); } while (*status & UART_LSR_DR); tty_flip_buffer_push(tty); + + info->wakeup_reason |= TIOCMIWAIT_RX; + } static _INLINE_ void transmit_chars(struct async_struct *info, int *intr_done) @@ -486,6 +497,10 @@ if (info->xmit_cnt < WAKEUP_CHARS) rs_sched_event(info, RS_EVENT_WRITE_WAKEUP); + /* enable waiting on tx queue empty */ + if (info->xmit_cnt == 0) + info->wakeup_reason |= TIOCMIWAIT_TX; + #ifdef SERIAL_DEBUG_INTR printk("THRE..."); #endif @@ -508,21 +523,27 @@ if (status & UART_MSR_ANY_DELTA) { icount = &info->state->icount; /* update input line counters */ - if (status & UART_MSR_TERI) + if (status & UART_MSR_TERI) { icount->rng++; - if (status & UART_MSR_DDSR) + info->wakeup_reason |= TIOCMIWAIT_RNG; + } + if (status & UART_MSR_DDSR) { icount->dsr++; + info->wakeup_reason |= TIOCMIWAIT_DSR; + } if (status & UART_MSR_DDCD) { icount->dcd++; + info->wakeup_reason |= TIOCMIWAIT_DCD; #ifdef CONFIG_HARD_PPS if ((info->flags & ASYNC_HARDPPS_CD) && (status & UART_MSR_DCD)) hardpps(); #endif } - if (status & UART_MSR_DCTS) + if (status & UART_MSR_DCTS) { icount->cts++; - wake_up_interruptible(&info->delta_msr_wait); + info->wakeup_reason |= TIOCMIWAIT_CTS; + } } if ((info->flags & ASYNC_CHECK_CD) && (status & UART_MSR_DDCD)) { @@ -616,6 +637,9 @@ if (status & UART_LSR_THRE) transmit_chars(info, 0); + /* on any int wake up a waiting task - if one exists */ + wake_up_interruptible(&info->delta_msr_wait); + next: info = info->next_port; if (!info) { @@ -686,6 +710,7 @@ break; } } while (!(serial_in(info, UART_IIR) & UART_IIR_NO_INT)); + wake_up_interruptible(&info->delta_msr_wait); info->last_active = jiffies; #ifdef CONFIG_SERIAL_MULTIPORT if (multi->port_monitor) @@ -743,6 +768,7 @@ if (status & UART_LSR_THRE) transmit_chars(info, 0); + wake_up_interruptible(&info->delta_msr_wait); next: info = info->next_port; if (info) @@ -1147,6 +1173,7 @@ * clear delta_msr_wait queue to avoid mem leaks: we may free the irq * here so the queue might never be waken up */ + info->wakeup_reason = 0; wake_up_interruptible(&info->delta_msr_wait); /* @@ -2028,12 +2055,56 @@ } #endif + +static int wait_for_serial_interrupt(struct async_struct * info, int arg) { + int reason; + unsigned long flags; + + save_flags(flags); cli(); + reason = info->wakeup_reason; + info->wakeup_reason = 0; + restore_flags(flags); + + /* + * interpret arg==0 as + * Tell me what interrupts have happened and + * Clear the slate. + */ + if( (arg==0) || (arg==TIOCMIWAIT_RETFLAGS)) + return reason; + + /* check that we can wake up */ + if( !( arg & (TIOCMIWAIT_RNG | TIOCMIWAIT_DSR | + TIOCMIWAIT_DCD | TIOCMIWAIT_CTS | + TIOCMIWAIT_RX | TIOCMIWAIT_BRK | + TIOCMIWAIT_TX | TIOCMIWAIT_ERR ) ) ) { + return -EPERM; + } + info->flags |=ASYNC_CALLOUT_ACTIVE|ASYNC_CALLOUT_NOHUP; + while (! (arg & reason)) { + interruptible_sleep_on(&info->delta_msr_wait); + /* see if a signal did it */ + if (signal_pending(current)) + return -ERESTARTSYS; + save_flags(flags); cli(); + reason = info->wakeup_reason; + info->wakeup_reason = 0; + restore_flags(flags); + } + info->flags &= ~(ASYNC_CALLOUT_ACTIVE|ASYNC_CALLOUT_NOHUP); + + if(arg & TIOCMIWAIT_RETFLAGS) + return reason; + + return 0; +} + static int rs_ioctl(struct tty_struct *tty, struct file * file, unsigned int cmd, unsigned long arg) { int error; struct async_struct * info = (struct async_struct *)tty->driver_data; - struct async_icount cprev, cnow; /* kernel counter temps */ + struct async_icount cnow; /* kernel counter temps */ struct serial_icounter_struct *p_cuser; /* user space */ unsigned long flags; @@ -2086,33 +2157,12 @@ * - mask passed in arg for lines of interest * (use |'ed TIOCM_RNG/DSR/CD/CTS for masking) * Caller should use TIOCGICOUNT to see which one it was + * + * First check to see if anything happened since the last time + * we were here. */ case TIOCMIWAIT: - save_flags(flags); cli(); - /* note the counters on entry */ - cprev = info->state->icount; - restore_flags(flags); - while (1) { - interruptible_sleep_on(&info->delta_msr_wait); - /* see if a signal did it */ - if (signal_pending(current)) - return -ERESTARTSYS; - save_flags(flags); cli(); - cnow = info->state->icount; /* atomic copy */ - restore_flags(flags); - if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && - cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) - return -EIO; /* no change => error */ - if ( ((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) || - ((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) || - ((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) || - ((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) { - return 0; - } - cprev = cnow; - } - /* NOTREACHED */ - + return wait_for_serial_interrupt(info,arg); /* * Get counter of input serial line interrupts (DCD,RI,DSR,CTS) * Return: write counters to the user passed counter struct